The invention is based on a fuel injection pump for internal combustion engines as defined hereinafter. A fuel injection pump of this kind, known from German Auslegeschrift 10 39 309, is provided with a single pump piston, which is coupled with a rotationally driven cam disk provided on the top and bottom with a cam track and which is guided between rollers of a cam ring, adjustably supported in the circumferential direction only, on the top and rollers of a corresponding cam ring on the bottom. By the passage of the cam track between the rollers, which are stationary in the axial direction, the cam disk and pump piston are caused to reciprocate and rotate simultaneously. The pump piston here serves as a distributor as well. The pump work chamber enclosed by the pump piston communicates during the intake stroke of the pump piston with a fuel supply line, in which an adjustable intake throttle is disposed, by way of which the quantity of fuel that is to be injected per pumping stroke is metered.
In distributor fuel injection pumps of the radial piston type, it is known for the pump pistons, which are supported radially in a rotationally drive distributor in pump cylinders, to be driven by means of a cam ring which radially surrounds the distributor and has faces which point radially inward. During the intake stroke the pump pistons are moved outward toward the cam ring, under the influence of the fuel pressure and centrifugal force, and during the pumping stroke they are moved inward once again, via roller shoes, by means of the cam elevations until reaching a dead center point that is determined by the cam height. In such pumps the fuel quantity is regulated via limiting the outward movement of the pistons, either by means of an adjustable stop or by means of a hydraulic limitation, in which during the intake stroke either the fuel supply is throttled or its timing is controlled. In these pumps, there is the disadvantage that a predetermined stroke sequence per unit of time, which is a product of the rpm and the number of pumping strokes per revolution, cannot be exceeded, because then the pump piston can no longer follow the cam track during the intake stroke unless special auxiliary means are provided. There are also limits on the use of restoring springs in such pumps. The problems associated with the pump piston rising from the cam track and with the vibrations of restoring springs are well known.